21980220 has 48 divisors (see below), whose sum is σ = 63214368. Its totient is φ = 5702400.

The previous prime is 21980197. The next prime is 21980243. The reversal of 21980220 is 2208912.

It is an interprime number because it is at equal distance from previous prime (21980197) and next prime (21980243).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2731 + ... + 7170.

It is an arithmetic number, because the mean of its divisors is an integer number (1316966).

Almost surely, 2^21980220 is an apocalyptic number.

21980220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21980220 is an abundant number, since it is smaller than the sum of its proper divisors (41234148).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21980220 is a wasteful number, since it uses less digits than its factorization.

21980220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9950 (or 9948 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 21980220 is about 4688.3067305798. The cubic root of 21980220 is about 280.1199316159.

The spelling of 21980220 in words is "twenty-one million, nine hundred eighty thousand, two hundred twenty".